ld/NEWS

   1 -*- text -*-
   2
   3 * Add support for GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
   4
   5 * Support for -z ibtplt in the x86 ELF linker to generate IBT-enabled
   6   PLT.
   7
   8 * Support for -z ibt in the x86 ELF linker to generate IBT-enabled
   9   PLT as well as GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
  10   properties.
  11
  12 * Add support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX.
  13
  14 * Add support for ELF GNU program properties.
  15
  16 * Add support for the Texas Instruments PRU processor.
  17
  18 * When configuring for arc*-*-linux* targets the default linker emulation will
  19   change if --with-cpu=nps400 is used at configure time.
  20
  21 * Improve assignment of LMAs to orphan sections in some edge cases where a
  22   mixture of both AT>LMA_REGION and AT(LMA) are used.
  23
  24 * Orphan sections placed after an empty section that has an AT(LMA) will now
  25   take an load memory address starting from LMA.
  26
  27 * Section groups can now be resolved (the group deleted and the group members
  28   placed like normal sections) at partial link time either using the new linker
  29   option --force-group-allocation or by placing FORCE_GROUP_ALLOCATION into the
  30   linker script.
  31
  32 Changes in 2.28:
  33
  34 * The EXCLUDE_FILE linker script construct can now be applied outside of the
  35   section list in order for the exclusions to apply over all input sections in
  36   the list.
  37
  38 * Add support for the RISC-V architecture.
  39
  40 * The command line option --no-eh-frame-hdr can now be used in ELF based
  41   linkers to disable the automatic generation of .eh_frame_hdr sections.
  42
  43 * Add --in-implib=<infile> to the ARM linker to enable specifying a set of
  44   Secure Gateway veneers that must exist in the output import library specified
  45   by --out-implib=<outfile> and the address they must have.  As such,
  46   --in-implib is only supported in combination with --cmse-implib.
  47
  48 * Extended the --out-implib=<file> option, previously restricted to x86 PE
  49   targets, to any ELF based target.  This allows the generation of an import
  50   library for an ELF executable, which can then be used by another application
  51   to link against the executable.
  52
  53 Changes in 2.27:
  54
  55 * Add a configure option --enable-relro to decide whether -z relro should
  56   be enabled in ELF linker by default.  Default to yes for all Linux
  57   targets except FRV, HPPA, IA64 and MIPS.
  58
  59 * Support for -z noreloc-overflow in the x86-64 ELF linker to disable
  60   relocation overflow check.
  61
  62 * Add -z common/-z nocommon options for ELF targets to control whether to
  63   convert common symbols to the STT_COMMON type during a relocatable link.
  64
  65 * Support for -z nodynamic-undefined-weak in the x86 ELF linker, which
  66   avoids dynamic relocations against undefined weak symbols in executable.
  67
  68 * The NOCROSSREFSTO command was added to the linker script language.
  69
  70 * Add --no-apply-dynamic-relocs to the AArch64 linker to do not apply link-time
  71   values for dynamic relocations.
  72
  73 Changes in 2.26:
  74
  75 * Add --fix-stm32l4xx-629360 to the ARM linker to enable a link-time
  76   workaround for a bug in the bus matrix / memory controller for some of
  77   the STM32 Cortex-M4 based products (STM32L4xx)
  78
  79 * Add a configure option --enable-compressed-debug-sections={all,ld} to
  80   decide whether DWARF debug sections should be compressed by default.
  81
  82 * Add support for the ARC EM/HS, and ARC600/700 architectures.
  83
  84 * Experimental support for linker garbage collection (--gc-sections)
  85   has been enabled for COFF and PE based targets.
  86
  87 * New command line option for ELF targets to compress DWARF debug
  88   sections, --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi].
  89
  90 * New command line option, --orphan-handling=[place|warn|error|discard], to
  91   adjust how orphan sections are handled.  The default is 'place' which gives
  92   the current behaviour, 'warn' and 'error' issue a warning or error
  93   respectively when orphan sections are found, and 'discard' will discard all
  94   orphan sections.
  95
  96 * Add support for LLVM plugin.
  97
  98 * Add --print-memory-usage option to report memory blocks usage.
  99
 100 * Add --require-defined option, it's like --undefined except the new symbol
 101   must be defined by the end of the link.
 102
 103 Changes in 2.25:
 104
 105 * PE binaries now once again contain real timestamps by default.  To disable
 106   the inclusion of a timestamp in a PE binary, use the --no-insert-timestamp
 107   command line option.
 108
 109 * Replace support for openrisc and or32 with support for or1k.
 110
 111 * Add support for the --build-id command line option to COFF based targets.
 112
 113 * x86/x86_64 pe-coff now supports the --build-id option.
 114
 115 * Add support for the Andes NDS32.
 116
 117 Changes in 2.24:
 118
 119 * Add LOG2CEIL() builtin function to the linker script language
 120
 121 * Add support for the Texas Instruments MSP430X processor.
 122
 123 * Add support for Altera Nios II.
 124
 125 * Add support for the V850E3V5 architecture.
 126
 127 * Add support for the Imagination Technologies Meta processor.
 128
 129 * --enable-new-dtags no longer generates old dtags in addition to new dtags.
 130
 131 * Remove linker support for MIPS ECOFF targets.
 132
 133 * Add ALIGN_WITH_INPUT to the linker script language to force the alignment of
 134   an output section to use the maximum alignment of all its input sections.
 135
 136 Changes in 2.23:
 137
 138 * Enable compressed debug section feature for x86/x86_64 pe-coff.
 139
 140 * Add support for the 64-bit ARM architecture: AArch64.
 141
 142 * Added SORT_NONE to the linker script language to disable section sorting.
 143
 144 * Add a linker-provided symbol when producing ELF output, '__ehdr_start'
 145   to point to the ELF file header (and nearby program headers) in the
 146   program's memory image.
 147
 148 * Add support for S12X processor.
 149
 150 * Add support for the VLE extension to the PowerPC architecture.
 151
 152 * Add support for the Freescale XGATE architecture.
 153
 154 * Add option -f FILE on AIX (for response file).
 155
 156 * Add support for the Renesas RL78 architecture.
 157
 158 * Add support for the Adapteva EPIPHANY architecture.
 159
 160 Changes in 2.22:
 161
 162 * --copy-dt-needed-entries is no longer enabled by default.  Instead
 163   --no-copy-dt-needed-entries is the default.
 164
 165 * INPUT_SECTION_FLAGS has been added to the linker script language
 166   to allow selection of input sections by section header section flags.
 167
 168 * Add support for the Tilera TILEPro and TILE-Gx architectures.
 169
 170 * Added SORT_BY_INIT_PRIORITY to the linker script language to permit
 171   sorting sections by numerical value of the GCC init_priority attribute
 172   encoded in the section name.
 173
 174 Changes in 2.21:
 175
 176 * Linker script expression evaluation is somewhat more sane.  This may
 177   break scripts that depend on quirks of the old expression evaluation.
 178
 179 * Turn off underscoring for x86_64 PE+-COFF targets.  For old behavior the
 180   option --enable-leading-mingw64-underscores can be used on configure of
 181   bfd.
 182
 183 * Add support for the TMS320C6000 (TI C6X) processor family.
 184
 185 * --add-needed renamed to --copy-dt-needed-entries in order to avoid confusion
 186   with --as-needed option.
 187
 188 * Extend .def file syntax by '== <ID>' for imports and exports. This allows
 189   to alias the import/export table name written in PE image.
 190
 191 * Add --exclude-all-symbols option to PE based linkers.  This prevents all
 192   symbols from automatically being exported.
 193
 194 * Add support for the Renesas RX processor.
 195
 196 * Add support for alpha-vms target.
 197
 198 Changes in 2.20:
 199
 200 * GNU/Linux targets now support the STB_GNU_UNIQUE symbol binding.  This is a
 201   GNU extension to the standard set of ELF symbol bindings.  The binding will
 202   be passed on to the dynamic linker which will make sure that in the entire
 203   process there is just one symbol with the given name and type in use.
 204
 205 * PE targets now support a GNU extension to allow the alignment of common
 206   common symbols to be specified.  This support uses custom options in
 207   the .drectve section, which will be disregarded by the native tools.
 208
 209 * PE targets now add primitive support for ELF version scripts; symbols
 210   are not versioned, but the local and global symbol visibility directives
 211   are respected when filtering symbols in auto-export mode.
 212
 213 * New option --no-export-dynamic to undo the effect of the -E and
 214   --export-dynamic options.
 215
 216 * ELF: --warn-alternate-em option to warn if an object has alternate
 217   ELF machine code.
 218
 219 * New script function REGION_ALIAS to add alias names to memory regions.
 220
 221 * PE targets no longer make use of the long section names PE extension to
 222   the COFF format when generating executable images, by default.  The old
 223   (slightly non-conformant) behaviour can still be invoked by using the
 224   new '--enable-long-section-names' command-line option.  It is also enabled
 225   automatically in the presence of un-stripped debug information, as GDB
 226   needs to be able to find the debug info sections by their full names.
 227
 228 * For GNU/Linux systems the linker will now avoid processing any relocations
 229   made against symbols of the STT_GNU_IFUNC type and instead emit them into
 230   the resulting binary for processing by the loader.
 231
 232 * --as-needed now links in a dynamic library if it satisfies undefined
 233   symbols in regular objects, or in other dynamic libraries.  In the
 234   latter case the library is not linked if it is found in a DT_NEEDED
 235   entry of one of the libraries already linked.
 236
 237 * Add a new command line option, -Ttext-segment ADDR, for ELF targets
 238   to set the address of the first byte of the text segment.
 239
 240 * Add support for Sunplus score architecture.
 241
 242 * Add new option --use-nul-prefixed-import-tables to ld for PE targets to
 243   allow fallback to old import table generation with null element prefix.
 244
 245 * Windows PE systems now support a new --exclude-modules-for-implib option,
 246   allowing users to partition object files and archive members between a DLL
 247   and its associated import library as they are generated during linking.
 248
 249 * Add support for Lattice Mico32 (lm32) architecture.
 250
 251 * Add CR16 ELF --embedded-relocs (used to embedded relocations into binaries
 252   for Embedded-PIC code) option.
 253
 254 * Add to the PE/PE+ targets the support of two different kinds of
 255   pseudo-relocations.  They can be selected by the switches
 256   --enable-runtime-pseudo-reloc-v1 and --enable-runtime-pseudo-reloc-v2.
 257   For the switch --enable-runtime-pseudo-reloc it uses for 32-bit
 258   runtime pseudo relocation version one, for 64-bit the version two.
 259
 260 Changes in 2.19:
 261
 262 * Linker scripts support a new INSERT command that makes it easier to
 263   augment the default script.
 264
 265 * Linker script input section filespecs may now specify a file within an
 266   archive by writing "archive:file".
 267
 268 * The --sort-common switch now has an optional argument which specifies the
 269   direction of sorting.
 270
 271 * The M68K linker now supports multiple GOT generation schemes controlled via
 272   the --got=<type> command line option.
 273
 274 * The ARM EABI linker will now generate stubs for function calls to symbols
 275   that are too far away.  The placement of the stubs is controlled by a new
 276   linker command line option: --stub-group-size=N.
 277
 278 Changes in 2.18:
 279
 280 * Linker sources now released under version 3 of the GNU General Public
 281   License.
 282
 283 * ELF: New --build-id option to generate a unique per-binary identifier
 284   embedded in a note section.
 285
 286 * Added support for National Semicondutor CompactRISC (ie CR16) target.
 287
 288 * -l:foo now searches the library path for a filename called foo,
 289   without converting it to libfoo.a or libfoo.so.
 290
 291 * Add a new command line option '--default-script=FILE' or '-dT FILE'
 292   which specifies a replacement for the built in, default linker
 293   script.
 294
 295 * ELF: Add -Bsymbolic-functions, --dynamic-list-cpp-new, which puts C++
 296   operator new and delete on the dynamic list, and --dynamic-list-data,
 297   builtin list for --dynamic-list, which puts global data symbols on the
 298   dynamic list.
 299
 300 * Add support for x86_64 PE+ target.
 301
 302 * Add support for Score target.
 303
 304 * ELF: Add --dynamic-list option to specify a list of global symbols
 305   whose references shouldn't be bound to the definition within the
 306   shared library, or a list of symbols which should be added to the
 307   symbol table in the executable.
 308
 309 * The default output section LMA has changed for allocatable sections from
 310   being equal to VMA, to keeping the difference between LMA and VMA the same as
 311   the previous output section in the same region.  This is a more useful
 312   default when using overlays and other cases where you specify an LMA
 313   differing from the VMA for some sections.
 314
 315 * New switch: --print-gc-sections to list any sections removed by garabge
 316   collection.
 317
 318 * ARM: Added --vfp11-denorm-fix option to work around an erratum in current
 319   VFP11 coprocessors.
 320
 321 Changes in 2.17:
 322
 323 * Support for the Infineon XC16X has been added by KPIT Cummins Infosystems.
 324
 325 * Modify the Linux linker search order to better match ld.so search order.
 326   Look for DT_NEEDED libraries in paths specified by ld.so.conf before
 327   searching the default directories, rather than vice versa.
 328   Use $prefix/etc/ld.so.conf if it exists, otherwise /etc/ld.so.conf.
 329
 330 * PE-COFF: Forward exports from DLL's can now be specified in .def files
 331   passed directly to ld.
 332
 333 * Support for the Z80 processor family has been added.
 334
 335 * Add support for the "@<file>" syntax to the command line, so that extra
 336   switches can be read from <file>.
 337
 338 Changes in 2.16:
 339
 340 * Support for the R_ARM_V4BX relocation as defined in the ARM AAELF
 341   specification has been added via the --fix-v4bx command-line option.
 342
 343 * New linker script construct AS_NEEDED(), which sets the --as-needed flag
 344   for input files listed inside of it.
 345
 346 * A new command-line option, --sysroot, can be used to override the
 347   default sysroot location.  It only applies to toolchains that were
 348   configured using --with-sysroot.
 349
 350 * New linker script functions: ORIGIN() and LENGTH() which return information
 351   about a specified memory region.
 352
 353 * Port to MAXQ processor contributed by HCL Tech.
 354
 355 * Added SEGMENT_START to the linker script language to permit the user to
 356   override the base address for a segment from the command-line.
 357
 358 * ELF: --warn-shared-textrel option to warn if adding a DT_TEXTREL to a shared
 359   object.
 360
 361 * Added SORT_BY_NAME and SORT_BY_ALIGNMENT to the linker script
 362   language to permit sorting sections by section name or section
 363   maximum alignment.
 364
 365 * Added a new linker command line switch, --sort-section name|alignment,
 366   to sort sections by section name or maximum alignment.
 367
 368 * ELF: --add-needed/--no-add-needed options to control if a DT_NEEDED tag
 369   should be added when a shared library comes from DT_NEEDED tags.
 370
 371 * Support for the crx-elf target added.
 372
 373 * Support for the sh-symbianelf target added.
 374
 375 * A new linker command line switch has been added which allows the hash table
 376   size to be set to a suitable prime value near to its argument.  This switch
 377   is --hash-size=<NUMBER>.  Also if the switch --reduce-memory-overheads is
 378   used, and --hash-size has not been used, then the default value will be set
 379   to 1021.
 380
 381 * Linker map files are now generated with an O(N) algorithm for finding symbols
 382   that are defined in each section.  This uses about 40% more memory for
 383   symbols than the old O(N^2) algorithm.  You can use the new
 384   --reduce-memory-overheads option to select the old algorithm; this option
 385   might also be used in the future to select similar tradeoffs.
 386
 387 Changes in 2.15:
 388
 389 * ELF: --as-needed/--no-as-needed options to control if a DT_NEEDED tag should
 390   be added only when a shared library is referenced.
 391
 392 * PE: --large-address-aware option to indicate executables support virtual
 393   addresses greater than 2 gigabytes.
 394
 395 * DWARF 2 support for i386pe added.
 396
 397 * The linker script operator DEFINED() will now yield 1 only for a symbol that
 398   is defined before the statement where DEFINED is used.
 399
 400 * The MIPS --embedded-relocs (used to embed relocations into binaries for
 401   Embedded-PIC code) is deprecated and will be removed in a future release.
 402
 403 * cr16c support added by NSC.
 404
 405 * m32r Linux (ELF) support added by Renesas.
 406
 407 * Improved linker's handling of unresolved symbols.  The switch
 408   --unresolved-symbols=<method> has been added to tell the linker when it
 409   should report them and the switch --warn-unresolved-symbols has been added to
 410   make reports be issued as warning messages rather than errors.
 411
 412 Changes in 2.14:
 413
 414 * Added support for Xtensa architecture.
 415
 416 * Added --with-sysroot configure switch to specify a target system root, for
 417   linking against a target filesystem image.
 418
 419 * Added --accept-unknown-linker-format to restore old linker behaviour (pre
 420   2.14) of silently accepting and linking in any files in an unknown binary
 421   file format.
 422
 423 * Added --no-omagic to undo the effects of the -N option.
 424
 425 * Support for Texas Instruments TMS320C4x and TMS320C3x series of
 426   DSP's contributed by Michael Hayes and Svein E. Seldal.
 427
 428 * Added --with-lib-path configure switch to specify default value for
 429   LIB_PATH.
 430
 431 * ARM port to QNX operating system added by Graeme Peterson.
 432
 433 * IP2K support added by Denis Chertykov.
 434
 435 Changes in 2.13:
 436
 437 * Support for the Fujitsu FRV architecture added by Red Hat. Models for FR400
 438   and FR500 included.
 439
 440 Changes in version 2.13:
 441
 442 * DEC VAX ELF support, by Matt Thomas.
 443
 444 Changes in version 2.12:
 445
 446 * Support for Don Knuth's MMIX, by Hans-Peter Nilsson.
 447
 448 * Support for the OpenRISC 32-bit embedded processor by OpenCores.
 449
 450 * Support for -z nocopyreloc in the x86 ELF linker, which disables
 451   production of copy relocs.  Warning: using this option may result in
 452   non-sharable applications.
 453
 454 * Support for -z combreloc in the ELF linker, which puts dynamic
 455   relocations against the same symbol together, so that dynamic linker
 456   can use an one-entry symbol lookup cache.
 457
 458 * Support for ELF SHF_MERGE section merging, by Jakub Jelinek.
 459
 460 Changes in version 2.11:
 461
 462 * Support for AMD x86-64 architecture, by Jan Hubicka, SuSE Labs.
 463
 464 * Support added for eliminating duplicate DWARF2 debug information by
 465   having the compiler generate the information in sections called
 466   .gnu.linkonce.wi.XXXX where XXXX is a checksum for the contents.  The
 467   linker then merges these sections together into the normal .debug_info
 468   section.
 469
 470 * The native ELF linker now searches the directories in DT_RUNPATH or
 471   DT_RPATH of a shared library for shared libraries needed by it.
 472
 473 * TI C54x support, by Timothy Wall.
 474
 475 * Added command line switch --section-start to set the start address of any
 476   specified section.
 477
 478 * Added ability to emit full relocation information in linked executables,
 479   enabled by --emit-relocs.  Some post-linkage optimization tools need
 480   this information in order to be able to correctly identify and perform
 481   symbol relative addressing in the event of changes in section contents
 482   (instructions being added or deleted, extending data sections, etc.)
 483
 484 * Support for i860, by Jason Eckhardt (preliminary, alpha quality).
 485
 486 * Support for CRIS (Axis Communications ETRAX series).
 487
 488 * Support for PDP-11 and 2.11BSD a.out format, by Lars Brinkhoff.
 489
 490 Changes in version 2.10:
 491
 492 * Added AT> to the linker script language to allow load-time allocation of
 493   sections into regions.
 494
 495 * Added garbage collection of unused sections, enabled by --gc-sections.
 496   It does require a bit of backend support; currently implemented are
 497   arm-elf, avr-elf, d10v-elf, fr30-elf, i386-elf, m32r-elf, m68k-elf,
 498   mcore-elf, mips-elf, mn10300-elf, ppc-elf, sh-elf, sparc-elf, and v850-elf.
 499   Others will ignore the option.
 500
 501 * Added SORT to the linker script language to permit sorting sections by file
 502   name or section name.
 503
 504 * Added EXTERN to the linker script language as an equivalent to the -u
 505   command-line option.
 506
 507 * Added ASSERT to the linker script language.
 508
 509 * Added EXCLUDE_FILE to the linker script language for further control over
 510   wildcard file names.
 511
 512 * Added -O option to optimize linker output (as of this writing, this only
 513   affects ELF shared library generation).
 514
 515 * The -e option now accepts a number as well as a symbol name.
 516
 517 * Added --no-undefined option to disallow undefined symbols when creating a
 518   shared library.
 519
 520 * The linker now issues a warning, not an error, for an undefined symbol when
 521   using -Bsymbolic; use the new --no-undefined option to get the old
 522   behaviour.
 523
 524 * Added --demangle and --no-demangle options.
 525
 526 Changes in version 2.9:
 527
 528 * Added SQUAD to the linker script language.
 529
 530 * New option --no-warn-mismatch.
 531
 532 * The MEMORY command now parses the attributes to determine where sections that
 533   are not placed in a specific memory region are placed.
 534
 535 Changes in version 2.8:
 536
 537 * Linker scripts may now contain shell wildcard characters for file and section
 538   names.
 539
 540 * The linker now supports symbol versions in ELF.
 541
 542 * The NOCROSSREFS command was added to the linker script language.
 543
 544 * The LOADADDR expression was added to the linker script language.
 545
 546 * MAX and MIN functions were added to the linker script language.
 547
 548 * The OVERLAY construct was added to the linker script language.
 549
 550 * New option --warn-section-align to warn when the address of an output section
 551   changes due to alignment of an input section.
 552
 553 * New options --filter/-F and --auxiliary/-f.
 554
 555 Changes in version 2.7:
 556
 557 * New option --cref to print out a cross reference table.
 558
 559 * New option --wrap SYMBOL.
 560
 561 * New option --no-whole-archive, to turn off the effect of --whole-archive.
 562
 563 * Input sections assigned to the output section /DISCARD/ in the linker script
 564   are not included in the output file.
 565
 566 * The SunOS and ELF linkers now merge stabs debugging information which uses
 567   the N_BINCL and N_EINCL stab types.  This reduces the amount of debugging
 568   information generated.
 569
 570 Changes in version 2.6:
 571
 572 * When an ELF section name is representable as a C identifier (this is not true
 573 of most ELF section names), the linker will automatically define symbols
 574 __start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the
 575 beginning and the end of the section.  This is used by glibc.
 576
 577   Addendum: Current versions of the linker (at least for version 2.18 onwards
 578 and possibly much earlier as well) place two restrictions on this feature:  The
 579 symbols are only implemented for orphaned sections, not for explicitly placed
 580 sections and they are PROVIDEd rather than being defined.
 581
 582 * When an ELF section named .gnu.warning is encountered in an input file, the
 583 contents of the section are displayed as an error message, and the section is
 584 not copied into the output file.  This is used by glibc.
 585
 586 * When an ELF section named .gnu.warning.SYMBOL is encountered in an input
 587 file, and the symbol SYMBOL is referenced by some object file, the contents of
 588 the section are displayed as an error message.  The section is not copied into
 589 the output file, unless doing a relocatable or shared link.  This is used by
 590 glibc.
 591
 592 * New options -split-by-reloc and -split-by-file.
 593
 594 * The linker now supports linking PIC compiled code on SPARC SunOS.  It can
 595 also create SPARC SunOS shared libraries, and, like the native SunOS linker,
 596 will do so whenever there is an undefined symbol in the link and neither the -e
 597 nor the -r option was used.
 598
 599 * The -rpath option may be used on SunOS to set the list of directories to be
 600 searched at run time.  This overrides the default of building the list from the
 601 -L options.
 602
 603 * The COFF linker now combines debugging information for structs, unions, and
 604 enums, so that even if the same type is defined in multiple input files it will
 605 only be defined once in the output file.  The --traditional-format switch will
 606 prevent this optimization.
 607
 608 Changes in version 2.5:
 609
 610 * The linker now supports linking against SunOS shared libraries.  It still can
 611 not link SunOS PIC (Position Independent Code) files, so it can not be used to
 612 generate shared libraries.
 613
 614 * The linker now supports linking against ELF shared libraries for the i386
 615 (UnixWare) and SPARC (Solaris).  It can also link ELF PIC files, and can be
 616 used to generate shared libraries.  Shared library generation is not well
 617 tested; please report any problems encountered.  The linker is now enabled for
 618 Solaris again.
 619
 620 * Eric Youngdale has contributed Linux support code, including linking against
 621 Linux a.out shared libraries.  The linker produces Linux QMAGIC binaries.
 622
 623 * The ELF backend has been converted to the new linker code.  To use the new
 624 ELF linker, each particular target requires a relocation function.  So far,
 625 this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix
 626 5), and HPPA ELF targets.
 627
 628 * The -( (--start-group) and -) (--end-group) options have been added to
 629 support searching a group of archives as though they were a single archive.
 630 This can also be used in a linker script, as GROUP ( files ).
 631
 632 * When a file is named on the command line, and the linker does not recognize
 633 it as an object file, the linker will now treat the file as a linker script
 634 file.  A linker script named in this way augments, but does not replace, the
 635 default linker script.
 636
 637 * The -warn-once option was added.  It causes the linker to only warn once per
 638 undefined symbol, rather than once per reference.
 639
 640 * The COFF backend has been converted to the new linker code.  As with ELF, to
 641 use the new linker, each particular target requires a relocation function.  So
 642 far, this function has been written for the i386, m68k, a29k and SH targets.
 643
 644 * The -V flag was made a synonym for -v, for SVR4 compatibility.  The old -V
 645 behaviour is available via --verbose.
 646
 647 Changes in version 2.4:
 648
 649 * New linker code, by Steve Chamberlain and Ian Taylor.  For a.out and ecoff
 650   formats (so far), this should result in considerable savings in time
 651   and memory used while linking; slightly poorer performance than
 652   before for formats not converted yet.
 653
 654 * Command-line parsing is no longer done with flex.  This means
 655   oddball characters in filenames won't get treated as argument
 656   separators.
 657
 658 * HP-PA ELF support, by Jeff Law.  (No SOM support yet.)
 659
 660 * Mach i386 support, by David Mackenzie.
 661
 662 * Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared
 663   libraries are not yet supported).
 664
 665 * COFF shared libraries (as on SCO) should work as well.
 666
 667 * The linker is disabled for Solaris.  (Actually, it was in 2.3 also, I just
 668   forgot to note it.)  Some of their C library routines don't work when
 669   statically linked, and the GNU linker doesn't support dynamic linking yet.
 670
 671 Changes in version 2.3:
 672
 673 * Weak symbols are now supported.
 674
 675 * ELF support has been added.  The linker has been bootstrapped on
 676   UnixWare and Solaris.
 677
 678 * Alpha OSF/1 support has been added (non dynamic linking only).
 679
 680 Changes in version 2.2:
 681
 682 * The `bfd' library has been updated to reduce a.out-format string
 683   table size.  The effect of this is that files linked from many input
 684   files with duplicate symbols (`-g' debugging records, or identical
 685   static symbols) should be much smaller.
 686
 687 Changes in version 2.1:
 688
 689 * The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented.
 690
 691 * There is now support for writing ECOFF files, so ld and the
 692   other utilities should work on Risc/Ultrix and Irix.
 693
 694 \f
 695 Copyright (C) 2012-2017 Free Software Foundation, Inc.
 696
 697 Copying and distribution of this file, with or without modification,
 698 are permitted in any medium without royalty provided the copyright
 699 notice and this notice are preserved.
 700
 701 Local variables:
 702 fill-column: 79
 703 End: